The subject matter disclosed herein relates to imaging systems, and more particularly to a positron emission tomography (PET) detector for a dual-modality imaging system.
In computed tomography (CT), X-ray radiation spans a subject of interest, such as a human patient, and a portion of the radiation impacts a detector where the image data is collected. In digital X-ray systems a photodetector produces signals representative of the amount or intensity of radiation impacting discrete pixel regions of a detector surface. The signals may then be processed to generate an image that may be displayed for review. In the images produced by such systems, it may be possible to identify and examine the internal structures and organs within a patient's body. In CT systems a detector array, including a series of detector elements, produces similar signals through various positions as a gantry is displaced around a patient, allowing volumetric reconstructions to be obtained.
It may be desirable to incorporate the functionality of a PET imaging system and the functionality of the CT imaging system in a dual-modality imaging system. At least one known PET imaging system includes a solid-state detector. The solid state detector includes an array of photodiodes that detect light impulses from an array of scintillation crystals. The photodiodes are typically mounted in close proximity to readout electronics to preserve the signal integrity of the photodiodes. In operation, the readout electronics generate heat that may affect the operation of the photodiodes. Accordingly, it is desirable to provide cooling for the PET detector. However, conventional cooling systems may create an adverse interaction with the CT imaging system. As a result, the addition of the PET detector within the CT imaging system may reduce the image effectiveness of either the CT imaging system or the PET imaging system.